James,
If you're just building a test bed. I wouldn't do the KMS activation at all. This is my opinion. I would configure back it up. when you put in the KMS client licenses, it will accept it but no need to activate it. Do regular backups..when the KMS keys try to check in...and it doesn't answer it will let you know. I would just reinstall and restore the backup. It takes a little longer but this way you not having to maintain a KMS server either.
The technet key may work but it has to be a KMS key and not an MAK key.
Cordially,
Ronnie Wong
Host, ITProTV